Accession Number:

ADA571169

Title:

Acoustic Blind Deconvolution and Frequency-Difference Beamforming in Shallow Ocean Environments

Descriptive Note:

Corporate Author:

MICHIGAN UNIV ANN ARBOR DEPT OF MECHANICAL ENGINEERING

Personal Author(s):

Report Date:

2012-01-01

Pagination or Media Count:

7.0

Abstract:

The overall long-term goal for this project is to develop engineering tools that are useful to the Navy as it operates in uncertain, partially known, or unknown ocean environments. During the last year, this project has focused on further determining the utility of a fully-passive propagation-physics-based technique for blind deconvolution of array-recorded sounds from a remote source with emphasis on determining how sparse-array measurements might be used for this task. The long term goals of this project are i to determine the effectiveness of synthetic time reversal STR for the purposes of blind deconvolution in noisy unknown ocean sound channels, ii to effectively apply STR to marine mammal sounds recorded in the ocean with vertical andor horizontal arrays, and iii to utilize the STR-estimated signals and ocean-sound-channel impulse responses to classify, localize, andor track individual marine mammals or other sound sources of interest. Since early 2009 this project has focused on developing an acoustic-ray-based version of synthetic time reversal STR, a fully-passive technique for recovering the original signal and the source-to-arrayelement impulse responses for a remote unknown sound source in an unknown underwater waveguide 1-4. The specific objectives are to a determine STR performance as a function of the signal-tonoise, array size, and array element number using acoustic propagation simulations, b verify these findings with simple airborne- or water-borne acoustic laboratory experiments involving multiple receivers and multiple ray paths, c obtain and process underwater array recordings of remote-butcooperative sound sources, and d obtain and process marine mammal vocalizations for the purposes of marine mammal localization, tracking, and identification. This research effort extends the prior modebased version of STR 1 to higher frequencies, smaller receiving arrays, sparse receiving arrays, and sound channels with modal dispersion

Subject Categories:

  • Hydrology, Limnology and Potamology
  • Acoustics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE